Mavic rear wheel hub is worn out

3600km, much of that over the winter, rear hub is noisy, grinding, slightly wobbly, Mavic XP22 with Shimano hub.
Buddy at the LBS says better just get a new wheel rather than replacing bits, keep the old one for next winter.
Thoughts ?

If it's Shimano hub, its a cup and cone jobbie and once the race is worn its a new hub. You could replace the hub and lace it up onto the existing rims and get your LBS to true it up, but in truth it might be just as much to get a replacement wheel.

Having said that, is it possible just to replace the freehub bearing? That sounds like it could be at least part of your problem.